WASHINGTON — (CNN) The inspector general for the intelligence community has informed members of Congress that some material emailed by Hillary Clinton from her private server contained classified information but because it was not identified that way, it is unclear if Clinton realized she was potentially compromising classified information, according to a spokeswoman for the IG’s office.

The IG reviewed a “limited sampling” of her emails and among those 40 found that “four contained classified [intelligence community] information,” wrote the IG Charles McCullough.

But McCullough noted “none of the emails we reviewed had classification or dissemination markings.”

The four emails in question “were classified when they were sent and are classified now,” spokeswoman Andrea Williams told CNN in a phone interview. But she added that they were never marked as classified and “should have been.”

McCullough said that the State Department FOIA officials told the intelligence community IG that “there are potentially hundreds of classified emails within the approximately 30,000 provided by former Secretary Clinton.”

The letter was first reported by The Wall Street Journal.

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